idle speed
Elder User
Joined: Mar 2006
Posts: 590
Likes: 1
From: Venetia, PA
Try cleaning the IAC valve. It is the large valve that is bolted to the throttle body and has a plug on the end. Unplug it and remove it. Take the two halves of the IAC apart by removing the two small screws and pulling it apart. Clean the valve side with carb cleaner or gumout. Do not spray carb cleaner or anything on the electronic side. If it looks dirty, wipe it off with a damp rag or a wet q-tip. Let both sides dry, put them back together and put it back on the throttle body. Disconnect the battery for a few minutes then reconnect it. Go for a short drive around town to let the computer relearn the correct idle. All this should help steady out your rough idle.
Last edited by mrl390; Sep 30, 2007 at 07:52 AM.
Elder User
Joined: Sep 2005
Posts: 841
Likes: 0
From: Orangeville, Ontario
I have a related question. My idle fluctuates like mad sometimes and I went ahead and replaced the IAC (dealer said it was bad) and it didn't cure it. But here's the thing, I'm not currently driving the truck just kinda bringing it back to beyond par before next spring. Is there anything I can do but wait til' I can take it for a drive for the computer to re-learn the idle?
Elder User
Joined: Mar 2006
Posts: 590
Likes: 1
From: Venetia, PA
If the idle is still fluctuating after the IAC replacement, I dont think its a matter of the computer relearning the idle. On mine, after cleaning, it ran at a high idle. After I disconnected the battery for a few minutes and took it for a drive, the idle slowed down. For your problem, I would try checking the codes. I wouldnt be surprised if you pulled codes 32 or 33 with the light off. Thats means the EVP (EGR valve position sensor) is bad, which is the electronic sensor on top of the EGR that tells it to open or close. If you can, remove the EGR and clean it out with some throttle body cleaner and replaced the EVP. This could be your problem, and even if its not, its one of those things that isnt a bad idea to do anyway. Pull the codes before you do tho.
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